SEBNITZ, Germany An East German town at the center of neo-Nazi allegations has canceled an anti-racism demonstration this weekend due to fears of disruption by left- and right-wing groups, the local mayor said Thursday.

The town of Sebnitz had wanted to use Sunday's demonstration to dispel the impression that it was a hotbed of neo-Nazism, even though the authorities have ruled out the possibility that the drowning of a six-year-old boy there three years ago was a racist crime.

But Mayor Mike Ruckh told Mitteldeutsche Rundfunk Radio that the demonstration was canceled due to threats of disruption from both leftist and rightist groups.

Ruckh said the cancelation was made in agreement with the Interior Ministry for Saxony State, where Sebnitz lies, and with the Domestic Federal Security Agency, the office for the protection of the Constitution.

Saxony's State prosecutor had Tuesday ruled out the possibility that six-year-old Joseph Kantelberg-Abdulla, who father is of Iraqi origin and whose mother is German, had been killed by neo-Nazis.

The prosecutor said Wednesday that he was investigating Joseph's mother, who had said her son was murdered by neo-Nazis when he drowned in a public swimming pool in Sebnitz in June 1997.

The witnesses who supported her claim that the death was not an accident have since retracted their statements, and one has even filed a complaint that the mother, Renate Kantelberg-Abdulla, had led him into false testimony.

Investigators were following up this complaint and also investigating three other witnesses, the prosecutor's office in Dresden said.

Later Wednesday the home of the parents, currently under police protection, was searched by local court officials, AFP said on Friday.

Meanwhile, the parents of the dead boy said they had been victims of a "hate campaign" and had "nothing to hide.

The family's allegations had sparked an outpouring of shock and indignation in Germany at the end of last week. The family had been recently in hiding in Bavaria under protection and undergoing psychiatric care, but had returned home, police said.

Saad Abdulla, the boy's Iraqi father, denied press reports that his wife Renate had paid witnesses to sign statements she had dictated.

According to the boy's parents, he had been drugged and tortured with an electric shock instrument before being deliberately drowned in the crowded pool by a gang of neo-Nazis on June 13, 1997.

The case was closed in 1998 with the conclusion that the boy had drowned accidentally, but was reopened on the basis of statements from witnesses. These have now retracted their testimony.

Joseph may have died as a result of a heart problem, according to a second autopsy carried out on the boy, it also emerged. The pathologist at the first autopsy has admitted he failed to examine the heart muscle.

The case was revealed with great publicity last Thursday by the mass-circulation Bild newspaper, whose Sunday edition also printed the alleged witness statements in detail.

By Wednesday it had back-pedaled hard, however. The paper's headlines said there was "Ever More Doubt About Joseph's Mother" and asked: "Who Still Believes Her Now?"